Adjustable chair



Aug. 25, 1959 c. c. DICKSON ADJUSTABLE CHAIR Filed Dec. 21, 1956 uvmvroxLlzfibrd 6. 252127010 BY W A TTOKNE Y5 2,901,027 Patented Aug. 25, 1959ADJUSTABLE CHAIR Clilford C. Dickson, St. Paul, Minn., assignor toMichael F. Murray, St. Cloud, Minn.

Application December 21, 1956, Serial No. 629,906

4 Claims. or. 155-160) This invention relates to adjustable chairs, andparticularly to chairs having resiliently swingable back rests whereinthe range of swinging movement may be adjusted and wherein the back restmay be locked in any of a plurality of fixed positions within its rangeof swinging movement.

In general, the invention comprises novel chair structure wherein aswinging back rest is connected to a seat support through the medium ofa control mechanism permitting rearward swinging of the back rest,against the action of spring means, from a forward position. Themechanism includes adjustment features whereby the so* called forwardposition may be changed in a fore-andaft direction with the back reststill free to resiliently swing throughout the same total range ofmovement from the different forward positions. The invention alsoincludes novel features of construction and means whereby the back restmay be rigidly locked at any one of a plurality of positions in itsrange of swinging movement.

It is therefore an object of this invention to provide a chair having aback rest mounted for resilient swinging movement throughout apredetermined angular range and wherein the starting position of saidrange may be adjusted at will.

It is another'object of this invention to provide novel adjustable chairstructure.

Still another object of the invention is to provide a novel chairstructure of simple construction, economical to manufacture, andreliable in operation.

Additional objects and advantages will become apparent to those skilledin the art as the description proceeds in connection with theaccompanying drawings, wherein:

Fig. 1 is a perspective View of a chair embodying the present inventionwith the back rest shown in different positions by dotted line;

Fig. 2 is a fragmentary sectional view taken substantially along theline 2-2 of Fig. 1 and on a somewhat enlarged scale;

Fig. 3 is a vertical sectional view taken along the line 3-3 of Fig. 2;and

Fig. 4 is a fragmentary perspective view of a portion of the structureof Figs. 2 and 3 with the parts shown in a somewhat exploded positionfor clarity of illustration.

Referring first to Fig. l, the chair comprises a usual or conventionalbase 2 provided with casters 4. A standard or post 6 extends through thebase 2 and may be vertically adjusted therein in any well-known orconvenient manner. At its upper end the standard 6 is provided with anenlarged head 8 (Figs. 2 and 3) rigidly secured to a seat frame 10. Theseat frame 10 may be cast or fabricated and may be integral withthe'standard 6 and its head 8, if desired. A seat cushion 12'is securedto the frame 10 and arm rests 14 are supported by side arms 16 which, inturn, are secured to pads 18 formed on the seat frame 10, by means ofscrews or the like 20.

The rear edge of the seat frame 10, (Fig. 2) is pro vided with a pair ofrearwardly extending loops or brackets 22. A generally U-shaped member24 comprises upright leg portions 26 extending through and pivoted inthe brackets or loops 22 on a common axis defined by pivot pins 28. Theleg portions 26 are rigidly joined at their bottom ends by thetransverse member 30 of the U-shaped element. The loops or brackets 22are sufficiently larger than the legs 26 to permit the U- shaped memberto swing about the horizontal axis defined by pins 28 throughout asubstantial angle of movement.

A U-shaped bracket 32 is secured, as by welding, to the transversemember 30 and is provided with a vertical slot 34 in the web portionthereof. A back rest panel 36 is provided with supporting legs 38extending downwardly therefrom and joined at their lower ends by atransverse plate 40. The plate 40 is provided with an intermediateopening (not identified) through which a securing means 42 passes. Themeans 42 comprises a conventional hand nut and bolt extending throughthe slot 34 in the bracket 32. As is obvious, the back rest panel 36 maybe adjusted vertically on the bracket 32 within the range permitted bythe slot 34 and is supported by the bracket 32 and U-shaped member 26for swinging movement about the horizontal axis of pins 28.

A pair of spaced brackets 44 are welded or otherwise securely fastenedto the forward side of the transverse member 30 and are provided withaligned openings loosely and pivotally supporting a first rod 46. A pairof threaded slide rods 48 is mounted on the rod 46 with each of the rodsof the pair adjacent a corresponding bracket 44 and with both rodsbetween the brackets 44. Transverse openings in the rod 46 are threadedto receive the slide rods 48, as shown. 6 The rods '48 thus hold the rod46 against endwise removal from the brackets 44 and serve to retain theassembly in the described relationship.

The enlarged head 8 of the standard 6 is provided with a forwardlyextending threaded stud 50 (see also Fig. 4) fixed thereon. A pair ofidentical bars 52 is provided. Each bar 52 has a central opening (notidentified) loosely embracing the stud 50 whereby the bars 52 areslidable along the stud 50 on the crests of the threads thereof. Eachbar 52 is further provided with an opening on each side of the centralopening in line with a corresponding opening in the other bar 52. The

slide rods 48, previously described, extend slidably through the spacedopenings near the ends: of the bars 52. The slide rods 48 are providedwith headed ends 54, as shown. A compression spring 56 surrounds eachrod 48 and at its forward end abuts the inner bar 52 while its rearrnostend abutsa nut 57 threadedly adjustable on the corresponding rod 48.

A nut 58 is threaded on the stud 50 inwardly of the inner bar 52 and asuitable hand nut 60 is threaded to the stud 50 outwardly of theoutermost bar 5-2.

It will be obvious that the transverse bars 52 constitute and abutmentdefining a reaction member for the springs 56. Thus, the back rest mayswing rearwardly, through the dotted line positions of Fig. l, whereuponthe slide rods 43 slide freely through the bars 52 and such movementeffects compression of springs 56. Obviously the compression of springs56 may be adjusted to predetermine the ease with which swinging movementof the back rest can be accomplished and to predetermine the range ofswinging movement from the forward position wherein the parts are in therelative positions shown in Figs. 2 and 3. By adjusting nuts 58 :and 60on the stud 50, the position of the bars 52 may be regulated tothereupon change the forward position of the back rest panel 36 to anydesired position (within. the limits of adjustment) and from thatforward position the back v 3 rest is capable of resilient swingingmovement through a full range of motion. It is to be noted that suchadjustment of the position of bars 52 does not change the compression onsprings 56.

As also clearly shown in Fig. 4, the slide rods 48 are provided withlongitudinally spaced notches 62 on their side edges adjacent theforward ends of those rods.- As shown, three such notches are providedon each red. A lever 64 is pivotally carried by the stud 50 between thebars 52 and is, in turn, provided with notches66 on opposed edgesthereof in position to engage the narrow portions of the rods 48, asdefined by the notches 62, when those notched portions are positioned inthe plane of the lever 64. The lever 64 is also provided with anextending handle portion 68 readily accessible to an occupant of thechair, as evident from Fig. 1.

By the structure thus far described, it will be obvious that the user ofthe chair may initially adjust the nuts '57 on slide rods 48 to regulatethe resilient resistance to swinging movement of the back rest 36. Then,by adjusting nut 58 and hand wheel 60 on stud 50, he may regulate thenormal or forward position of the back rest panel 36 within a relativelywide range, positioning it to normally occupy a desired position. Withthe handle 68 of the lever 64 then in its uppermost position, whereinnotches 66 are free of the rods 48, the hand nut 60 may be tightened toclamp the lever 64 in such position and the chair may be used asdesired. In this condition. of adjustment the user may lean back on theback rest 36 and cause it to resiliently swing through the dotted linepositions of Fig. 1 and return, at will. By loosening the hand nut 60the user may then swing the back rest to a dotted line position whereinselected notches 62 in the rods 48 are aligned with the lever 64whereupon the handle 68 of lever 64 may be depressed to the position ofFig. 4, which thereby locks the rods 48 against sliding movement throughbars 52 and hand nut 60 may be then tightened to lock the lever 64 inthe described position. In that position the back rest panel 36 is inthe selected angular position and lockd therein against swingingmovement in either direction. 'It is to be noted that, even though onlythree notches 62 are provided, the panel 36 may be locked in any desiredangular position by selecting the nearest notches 62 for engagement bylever 64 and then adjusting the position of bars 52 along stud 50 untilthe selected locked position of panel 36 is at the angle desired.

The mechanism described herein thus provides a multitude of adjustmentsand selectable positions for a back rest, in accordance with theaforesaid objects.

While a single specific embodiment of the invention has been shown anddescribed herein, it is to be understood that the form shown is merelyillustrative. It is 4 contemplated that the invention encompass otherembodiments falling within the scope of the appended claims.

I claim:

1. In a chair having a seat support and an upstanding back rest pivotedthereto on a horizontal axis, a control structure comprising relativelyslidable first and second portions, spring means urging said portions torelatively extended positions in a fore-and-aft direction, said firstportion being mounted on said seat support and said second portion beingconnected to said back rest below said axis, means for adjusting theposition of said first portion on said seat support in a fore-and-aftdirection, and locking means for locking said portions against relativesliding in any selected one of a plurality of predetermined relativepositions thereof.

2. A chair as defined in claim 1 wherein said first portion comprises atransverse bar structure having an opening therethrough, said secondportion including a rod slidable through said opening, a lever pivotallymounted on said seat support adjacent said bar structure and having anotch in an edge thereof, longitudinally spaced notches in said rod,said notch in said lever being engageable with a selected notch of saidrod to lock said rod against sliding movement in said opening.

3. A chair as defined in claim 2 including means for selectively lockingsaid lover against pivotal movement.

4. A chair as defined in claim 1 wherein said seat support includes athreaded stud fixed thereon and extending forwardly thereon, said firstportion comprising a pair of bars having central openings therethroughslidably embracing said stud, a lever pivoted on said stud between saidbars, said bars having aligned openings therethrough spaced from saidstud and on opposite sides thereof, said second portion including spacedparallel rods extending slidably through said aligned openings and eachhaving a plurality of notches in the sides thereof, said lever havingnotches in the edges thereof engageable with said rods at the notchestherein to lock said rods against sliding movement in said openings, anut threaded on said stud inwardly of said first portion, and a handwheel threaded on said stud outwardly of said first portion.

References Cited in the file of this patent UNITED STATES PATENTS1,849,073 Collier Mar. 15, 1932 1,973,627 Hatter Sept. 11, 19342,093,319 Herold Sept. 14, 1937 2,208,561 JungBauer ...2 July 23, 19402,249,750 Dickson July 22, 1941 2,410,871 Fields Nov. 12, 1946'2,518,946 Sickert Aug. 15, 1950 2,557,736 Fox June 19, 1951

